dbus-1.0/dbus/dbus-macros.h

0001 /* -*- mode: C; c-file-style: "gnu"; indent-tabs-mode: nil; -*- */
0002 /* dbus-macros.h  generic macros
0003  *
0004  * Copyright (C) 2002  Red Hat Inc.
0005  *
0006  * SPDX-License-Identifier: AFL-2.1 OR GPL-2.0-or-later
0007  *
0008  * Licensed under the Academic Free License version 2.1
0009  *
0010  * This program is free software; you can redistribute it and/or modify
0011  * it under the terms of the GNU General Public License as published by
0012  * the Free Software Foundation; either version 2 of the License, or
0013  * (at your option) any later version.
0014  *
0015  * This program is distributed in the hope that it will be useful,
0016  * but WITHOUT ANY WARRANTY; without even the implied warranty of
0017  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
0018  * GNU General Public License for more details.
0019  *
0020  * You should have received a copy of the GNU General Public License
0021  * along with this program; if not, write to the Free Software
0022  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
0023  *
0024  */
0025 #if !defined (DBUS_INSIDE_DBUS_H) && !defined (DBUS_COMPILATION)
0026 #error "Only <dbus/dbus.h> can be included directly, this file may disappear or change contents."
0027 #endif
0028
0029 #ifndef DBUS_MACROS_H
0030 #define DBUS_MACROS_H
0031
0032 #ifdef  __cplusplus
0033 #  define DBUS_BEGIN_DECLS  extern "C" {
0034 #  define DBUS_END_DECLS    }
0035 #else
0036 #  define DBUS_BEGIN_DECLS
0037 #  define DBUS_END_DECLS
0038 #endif
0039
0040 #ifndef TRUE
0041 #  define TRUE 1
0042 #endif
0043 #ifndef FALSE
0044 #  define FALSE 0
0045 #endif
0046
0047 #ifndef NULL
0048 #  ifdef __cplusplus
0049 #    define NULL        (0L)
0050 #  else /* !__cplusplus */
0051 #    define NULL        ((void*) 0)
0052 #  endif /* !__cplusplus */
0053 #endif
0054
0055 #if  __GNUC__ > 3 || (__GNUC__ == 3 && __GNUC_MINOR__ >= 1)
0056 #  define DBUS_DEPRECATED __attribute__ ((__deprecated__))
0057 #elif defined(_MSC_VER) && (_MSC_VER >= 1300)
0058 #  define DBUS_DEPRECATED __declspec(deprecated)
0059 #else
0060 #  define DBUS_DEPRECATED
0061 #endif
0062
0063 #if __GNUC__ > 2 || (__GNUC__ == 2 && __GNUC_MINOR__ >= 8)
0064 #  define _DBUS_GNUC_EXTENSION __extension__
0065 #else
0066 #  define _DBUS_GNUC_EXTENSION
0067 #endif
0068
0069 #if     (__GNUC__ > 2 || (__GNUC__ == 2 && __GNUC_MINOR__ > 4)) || \
0070          defined(__clang__)
0071 #define _DBUS_GNUC_PRINTF( format_idx, arg_idx )    \
0072   __attribute__((__format__ (__printf__, format_idx, arg_idx)))
0073 #define _DBUS_GNUC_NORETURN                         \
0074   __attribute__((__noreturn__))
0075 #define _DBUS_GNUC_UNUSED                           \
0076   __attribute__((__unused__))
0077 #else   /* !__GNUC__ */
0078 #define _DBUS_GNUC_PRINTF( format_idx, arg_idx )
0079 #define _DBUS_GNUC_NORETURN
0080 #define _DBUS_GNUC_UNUSED
0081 #endif  /* !__GNUC__ */
0082
0083 #if    __GNUC__ > 2 || (__GNUC__ == 2 && __GNUC_MINOR__ >= 96)
0084 #define DBUS_MALLOC     __attribute__((__malloc__))
0085 #else
0086 #define DBUS_MALLOC
0087 #endif
0088
0089 #if     (__GNUC__ > 4) || (__GNUC__ == 4 && __GNUC_MINOR__ >= 3)
0090 #define DBUS_ALLOC_SIZE(x) __attribute__((__alloc_size__(x)))
0091 #define DBUS_ALLOC_SIZE2(x,y) __attribute__((__alloc_size__(x,y)))
0092 #else
0093 #define DBUS_ALLOC_SIZE(x)
0094 #define DBUS_ALLOC_SIZE2(x,y)
0095 #endif
0096
0097 /** @def _DBUS_WARN_UNUSED_RESULT
0098  *
0099  * An attribute for functions whose result must be checked by the caller.
0100  *
0101  * This macro is used in function declarations. Unlike gcc-specific
0102  * attributes, to avoid compilation failure with MSVC it must appear
0103  * somewhere before the function name in the declaration. Our preferred
0104  * coding style is to place it before the return type, for example:
0105  *
0106  * DBUS_PRIVATE_EXPORT _DBUS_WARN_UNUSED_RESULT
0107  * dbus_bool_t _dbus_user_database_lock_system (void);
0108  */
0109 #if     defined(_MSC_VER) && (_MSC_VER >= 1700)
0110 #define _DBUS_WARN_UNUSED_RESULT _Must_inspect_result_
0111 #elif    (__GNUC__ > 3) || (__GNUC__ == 3 && __GNUC_MINOR__ >= 4)
0112 #define _DBUS_WARN_UNUSED_RESULT __attribute__((warn_unused_result))
0113 #else
0114 #define _DBUS_WARN_UNUSED_RESULT
0115 #endif
0116
0117 /** @def _DBUS_GNUC_PRINTF
0118  * used to tell gcc about printf format strings
0119  */
0120 /** @def _DBUS_GNUC_NORETURN
0121  * used to tell gcc about functions that never return, such as _dbus_abort()
0122  */
0123
0124 /* Normally docs are in .c files, but there isn't a .c file for this. */
0125 /**
0126  * @defgroup DBusMacros Utility macros
0127  * @ingroup  DBus
0128  * @brief #TRUE, #FALSE, #NULL, and so on
0129  *
0130  * Utility macros.
0131  *
0132  * @{
0133  */
0134
0135 /**
0136  * @def DBUS_BEGIN_DECLS
0137  *
0138  * Macro used prior to declaring functions in the D-Bus header
0139  * files. Expands to "extern "C"" when using a C++ compiler,
0140  * and expands to nothing when using a C compiler.
0141  *
0142  * Please don't use this in your own code, consider it
0143  * D-Bus internal.
0144  */
0145 /**
0146  * @def DBUS_END_DECLS
0147  *
0148  * Macro used after declaring functions in the D-Bus header
0149  * files. Expands to "}" when using a C++ compiler,
0150  * and expands to nothing when using a C compiler.
0151  *
0152  * Please don't use this in your own code, consider it
0153  * D-Bus internal.
0154  */
0155 /**
0156  * @def TRUE
0157  *
0158  * Expands to "1"
0159  */
0160 /**
0161  * @def FALSE
0162  *
0163  * Expands to "0"
0164  */
0165 /**
0166  * @def NULL
0167  *
0168  * A null pointer, defined appropriately for C or C++.
0169  */
0170 /**
0171  * @def DBUS_DEPRECATED
0172  *
0173  * Tells the compiler to warn about a function or type if it's used.
0174  * Code marked in this way should also be enclosed in
0175  * @code
0176  * #ifndef DBUS_DISABLE_DEPRECATED
0177  *  deprecated stuff here
0178  * #endif
0179  * @endcode
0180  *
0181  * Please don't use this in your own code, consider it
0182  * D-Bus internal.
0183  */
0184 /**
0185  * @def _DBUS_GNUC_EXTENSION
0186  *
0187  * Tells gcc not to warn about extensions to the C standard in the
0188  * following expression, even if compiling with -pedantic. Do not use
0189  * this macro in your own code; please consider it to be internal to libdbus.
0190  */
0191
0192 /*
0193  * @def DBUS_EXPORT
0194  *
0195  * Declare the following symbol as public.  This is currently a noop on
0196  * platforms other than Windows.
0197  */
0198
0199 #if defined(DBUS_EXPORT)
0200   /* value forced by compiler command line, don't redefine */
0201 #elif defined(_WIN32)
0202 #  if defined(DBUS_STATIC_BUILD)
0203 #  define DBUS_EXPORT
0204 #  elif defined(dbus_1_EXPORTS)
0205 #  define DBUS_EXPORT __declspec(dllexport)
0206 #  else
0207 #  define DBUS_EXPORT __declspec(dllimport)
0208 #  endif
0209 #elif defined(__GNUC__) && __GNUC__ >= 4
0210 #  define DBUS_EXPORT __attribute__ ((__visibility__ ("default")))
0211 #else
0212 #define DBUS_EXPORT
0213 #endif
0214
0215 /* Implementation for dbus_clear_message() etc. This is not API,
0216  * do not use it directly.
0217  *
0218  * We're using a specific type (T ** and T *) instead of void ** and
0219  * void * partly for type-safety, partly to be strict-aliasing-compliant,
0220  * and partly to keep C++ compilers happy. This code is inlined into
0221  * users of libdbus, so we can't rely on it having dbus' own compiler
0222  * settings. */
0223 #define _dbus_clear_pointer_impl(T, pointer_to_pointer, destroy) \
0224   do { \
0225     T **_pp = (pointer_to_pointer); \
0226     T *_value = *_pp; \
0227     \
0228     *_pp = NULL; \
0229     \
0230     if (_value != NULL) \
0231       destroy (_value); \
0232   } while (0)
0233 /* Not (destroy) (_value) in case destroy() is a function-like macro */
0234
0235 /** @} */
0236
0237 #endif /* DBUS_MACROS_H */